Cell staining is a technique that can be used to better visualize cells and cell components under a microscope. By using different stains, one can preferentially stain certain cell components, such as a nucleus or a cell-membrane, or the entire cell. Most stains can be used on fixed, or non-living cells, while only some can be used on living cells.
Electroluminescent compounds like platinum(II) complexes gained more and more attention recently. WO 2009/111299 discloses a platinum(II) complex in which three aromatic systems together form a tridentate ligand coordinated to a platinum ion through atoms X, Y and Z. The complexes are asymmetric and emit in the UV to near IR range. They are intended for use in organic light emitting devices.
Platinum complexes are also used in tumour therapy as they intercalate with DNA. This means that those complexes are toxic, which is a problem for their use in cell staining, especially in in vivo staining of cells.